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Torque Converters...Which one??

japslpr

japslpr

New member
Well, I gotta replace my Torque Converter....again. And I'm wanting some opinions on which one to use. 245mm or 258mm? Any advantages or disadvantages? Looking to go with 2750 - 3000 stall.
 


3000 stall is plenty, also what a stock converter will stall to. With your setup you have the potential to lay down some pretty healthy numbers and an aftermarket converter may be the safest option-though you havent had the best luck :( . My converters are $574.95 and are custom built to match your combo, have a 2 year warranty, and one free stall change.
 
Trannyman95 said:
3000 stall is plenty, also what a stock converter will stall to. With your setup you have the potential to lay down some pretty healthy numbers and an aftermarket converter may be the safest option-though you havent had the best luck :( . My converters are $574.95 and are custom built to match your combo, have a 2 year warranty, and one free stall change.
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2 of my previous converters have been 245mm converters from Transtar. I had a 2200(FDKB)B-21-5W and a 2800(FKBB) B-21-8W. Please see attachment for what I am talking about.

The latest converter I have which is in the car now is a 245mm Pro Torque I think. It is Green and has TCC 350 marked on it. I believe this is a 3500stall.

So should I use a 258mm converter instead of the 245mm? It states that the 245mm's I have been using from transtar are Woven Graphite material.

If I go 258mm, should I use the JTFM(stock) or the JXFM which I think you said was in the new 5.3GXP V8 models. I can't afford 575.00 for a converter right now. :(

Thanks
 

Attachments

The JXFM is the highest stall option for the 258mm converters. I prefer using them as they have a slightly larger lockup clutch surface than the 245mm converters and also seem to be a little tigher on the top end. I have run lots of 258mm converters in cars down into the low 12s and never had one fail
 
Trannyman95 said:
The JXFM is the highest stall option for the 258mm converters. I prefer using them as they have a slightly larger lockup clutch surface than the 245mm converters and also seem to be a little tigher on the top end. I have run lots of 258mm converters in cars down into the low 12s and never had one fail
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I'm shooting for the high 11's with this car. 11.9-11.8 Will the JXFM hold up for those times?
 


It should work fine. Buying an aftermarket one would be best and more durable but you should be fine for a while with a reman replacement and it may last indefinately. There are a number of local guys that I built transmissions for and a few deep into the low 12s with 140K mile original torque converters, that speaks for itself to me :th_thumbsup-wink:
 
Trannyman95 said:
It should work fine. Buying an aftermarket one would be best and more durable but you should be fine for a while with a reman replacement and it may last indefinately. There are a number of local guys that I built transmissions for and a few deep into the low 12s with 140K mile original torque converters, that speaks for itself to me :th_thumbsup-wink:
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How do you feel about the aftermarket converters ZZP, Intense and W-body store sell?

ZZP states that there converter is superior to all on the market. Using a kevlar clutch material and is 245mm. They do not disclose who they have manufacture there converters.

Intense is using ATI converters. Haven't heard much about them, but they also use the 245mm.

W-body store looks like the zzp converters.
 
The main reason I looked for a long time for a converter builder is because most places use Kevlar... Which is a very poor choice of friction material for a PWM type lockup system that always allows slippage which is what the 4T65E does. Big performance companies quit using Kevlar years ago because it does not work well in a torque converter and I am shocked to see anyone still use it because of the long trail of problems it has caused over the years. ZZP converters definately have the best track record over time but I have never and will never prefer using Kevlar for a lockup clutch and this is one reason that when you run their converters you have to bump up the numbers in the lockup MIN apply % tables, which really isnt a big deal but there is no way around the pcm wanting to see slippage, unless modifications are made but lets avoid that for now. My converters are built with a proprietary lockup clutch material that was designed specifically to be used in a PWM system so no changes are required to the tune for proper operation. Kevlar is such a hard material it will actually chew the metal up inside the converter body before the friction material wears, that and it is known to chatter and not have very good bite. Also my converters have a 2 year 100% warranty and that is something that pretty much no other converter on the market has. Like I have been telling people for years about torque converters, you get what you pay for plain and simple. If you want to go the cheap route on a performance converter than as I mentioned earlier ZZP converters have the best track record. I know nothing about Wbody store converters and have heard of only one guy that used one and went back to stock along the way. Something else to think about here.... How many STOCK converter failures do you read about?? I cant recal any. How many aftermarket vendor supplied converter failures do you read about?? There are more than enough out there to warrant against them and that is why I prefer stock remans because they work and are reliable. It is up to you and is your money, just beware the possibilities of failures and when torque converters go bad they fill the whole trans with metal debris which makes the rebuild twice as bad as the first time.
 
Thanks Dave. I think I am going to go with a JXFM 258mm conveter for now. It is a stock reman, but it should work until I can save for one of your converters or until this one fails, whichever comes first. But hey, rebuilding the tranny is nothing new to me...hahaha :rolleyes:
 


Trannyman95 said:
LOL yeah I feel bad every time you call! That converter should work just fine for you.
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No need to feel bad. It is just always something stupid that happens.

Hey 2 more questions for ya.

1. Remember I said that the 1-2 shift slips when I'm in L1 or D2. I know you said that is not a good thing to do and I don't much. However, if the gasket between the channel plate and the tranny case is blown out at the passage where the fluid travels when in L1 or D2, what should I look for as the cause of the gasket failing again? I made real sure that the gasket was lined up properly, not pinched or ripped and tightened down in the correct sequence. Mabe a straight edge on the channel plate mating surface? Too much pressure?

2. Why would a TC have a coast relief valve in it?
 
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If your gasket is blown out again here is one thing you can try... Using a center punch dimple the entire mating surface on the transmission case so there is some bite on the gasket. DONT use any kind of sealant or gasket cement as I have only seen this cause more blow-out problems contrary to what is believed in the trans world. Torque your bolts to 10 ft/lbs instead of the recommended 8
 
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